# Relationship history for MSHA mine 0503593

Current hierarchy: **Harmond George M → Mountain States Machinery & Supply Inc → Marion Canyon**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-13T11:19:05.459773+00:00

## Valid-time edges

- **operator_operates_mine:** Mountain States Machinery & Supply Inc → Marion Canyon; 1980-09-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Harmond George M → Marion Canyon; 1980-09-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Harmond George M → Mountain States Machinery & Supply Inc; 1980-09-01 to current/open; source msha-controller-operator-history